Roller bit



Patented July 28, 1931 PATENT OFFICE GUY E. BERNIE, OF HOUSTON,

TEXAS, ASSIGNOR TO IRE-ED ROLLER BIT COMPANY, OF

HOUSTON, TEXAS, A CORPORATION OF TEXAS ROLLER IBIT I Application \fi1ed June 10, 1929. Serial No. 369,571.

This invention relates to deep well drilling apparatus and more particularly to roller its.

All roller bit heads of the conventional type are provided with slush passageways leading to the roller cutters; and slush is pumped through these passageways primarily to cool the cutters and to remove the cuttings.

In one type of bit now in common use, the bearing surfaces of the roller cutters are continuously supplied with oil by means of a lubricant container in communication therewith and a device to force the oil from the 1:, container to the bearing surfaces.

of bit is illustrated by the patent to Hughes, No. 930,759 of August th, 1909.

Another type of bit in common use relies for lubrication of the bearing surfaces of its 2') roller cutters upon the slush forced through the bit head. Slush comprises muddy water and has lubricating properties. This type of bit, however, embodies no means especially adapted to convey a portion of the slush to the bearing surfaces. The patent to Duda, No. 1,660,309 of February21st, 1928, is illustrative.

The present invention has for its principal object the provision 'in a roller bit of so new and improved means for the utilization of slush to lubricate and cool roller cutter bearings.

Another object is to provide new and improved means to convey slush to the cutting teeth of a roller cutter to cool and clean the same.

Other objects will hereinafter appear. In the accompanying drawings, Fig. 1 is a side elevation partly in section of one embodiment of my invention; and Fig. 2, a horizontal section on the line 2-2 of Fig. 1.-

The bit head 1 shown by the drawings comprises a pair of longitudinally divided sec- 5 tions held together by the ring 2 and the screw-threaded shank 3, the latter of Wl'llCll may be screwed into theusual drill stem, not .shown. The lower ends of the sections of the head are beveled to form an inverted V-shaped cutter recess 4 into which project This type cutter spindles 5 to support substantially conical roller cutters 6.

As will hereinafter appear, many details of construction of the general elements referred to are immaterial to this invention. And it may here be remarked that the cutter 6 and the mounting therefor will constitute the subject matter-of other applications to be filed.

The sections of the bit head are recessed to form an axial slush passageway 7 extending through the head. Slush may, therefore, be pumped in the usual manner through the head and upon the cutters.

In this slush passageway I prefer to place a cylindrical strainer 8, which is held in place by its annular flange 8a fitting in an internal recess in the head. The apertures 8b of this strainer communicate with an annular space 9 between the strainer and the head. This space is connected to the bearing surfaces of the roller cutter 6 by the duct 1a in the head and grooves 5a in the spindle 5; and the cutter 6 has an opening 6a in its apex through which the slush may escape.

The major portion of the slush forced down in the drill stemunder great pressure passes downwardly through the strainer 8 and upon the roller cutters 6. The minor portion of it will be forced through the apertures 8?), space 9, duct 1a, grooves 5a and finally out through the opening 6a in the cutter 6. The bearing surfaces of the cutter are, therefore, completely and continually covered by slush moving thereover; and are therl'eby most efficiently lubricated and kept coo Furthermore, the slush escaping at the points of the cutters through the openings 6a cools and cleans the teeth adjacent thereto.

The invention will be found useful in various bits other than the type shown; and embodiments for use therein will readily occur to those skilled in the art.

7 The following claims are, therefore, not limited to the use or embodiment shown.

I claim:

1. A roller bit having a head, a spindle carried by said head, a roller cutter mounted on said spindle, said spindle having -a groove leading to the bearing surfaces of said cutter, said head having a slush passageway and a duct leading from said passageway and communicating with said groove, and a screen in said passageway over said duct.

2. In a roller bit, a head, a spindle carried by said head, a roller cutter mounted on said spindle, said spindle having a groove leading to the bearing surfaces of said cutterysaid head having a slush passageway extending therethrough, and a duct leading from the wall of said passageway and communicating with said groove, and a cylindrical apertured pipe in said passageway and spaced from the wall thereof.

3. A roller bit having a head, said head having an inverted V-shaped recess in the bottom thereof, spindles on said head projecting downwardly and inwardly into said recess, and substantially conical roller cutters on said spindles, each of said spindles having a groove leading to the bearing surfaces of the cutter thereon, said head having a slush passageway extending therethrough, and ducts leading from said passageway and communicating with said grooves, each of.

said cutters having a slush exit opening in the apex thereof.

4:. A roller bit having a head, said head having an inverted V-shaped recess in the bottom thereof, spindles on said head projecting downwardly and inwardly into said recess, substantially conical roller cutters on said spindles, each of said'spindles having a groove leading to the bearing surfaces of the cutter thereon, said head having a slush passageway extending therethrough, and ducts leading from the wall of said passageway and communicating with said grooves, each of said cutters having a slush exit opening in the apex thereof, and an apertured cylindrical pipe in said passageway and spaced from the wall thereof.

In testimony whereof, I hereuntoaflix my signature.

GUY E. BEHNKE. 

